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41.
The relative effect of residue of leaf, flower, stem, and root of parthenium (Parthenium hysterophorus L.) on growth of water hyacinth was studied. The inhibitory activity of the residue as shown by its effect on biomass and healthy leaf number (HLN) of treated plants was in the order: leaf and flower >stem >root. Total phenolic acids in the medium after 72 hr of suspending the plant part residue were maximum in flower followed by leaf, root, and stem, successively. The dry leaf powder (DLP) and dry flower powder (DFP) at and above 0.50% (w/v) and dry stem powder (DSP) at 1.00% (w/v) killed water hyacinth in about one month. Dry root powder (DRP) at the highest dose (1.25% w/v) reduced the growth of the treated plants drastically, but the plants recovered after about one month. The DSP at 0.50% (w/v) and DRP at 0.25–0.75% (w/v) supported growth of treated plants, probably due to lower levels of inhibitors, allowing utilization of constituents of the residue as nutrients. Using wheat seedlings as a reference material, it was observed that in aquaculture at different levels of parthenium plant parts residue, water hyacinth plants were much more sensitive to inhibitory activity. Thus, water hyacinth is suggested as a material for bioassay of inhibitory activity of the parthenium plant residue.  相似文献   
42.
Densification of Alumina and Silica in the Presence of a Liquid Phase   总被引:9,自引:0,他引:9  
Alumina and silica powders were sintered at 1250° to 1460°C in the presence of liquid phases containing CaO, A12O3, and SiO2. The data were analyzed using the equation D = K log t +C and the Arrhenius equation. The activation energy for sintering decreases with increasing amounts of liquid phase.  相似文献   
43.
In the current study a meshfree Lagrangian particle method for the Landau–Lifshitz Navier–Stokes (LLNS) equations is developed. The LLNS equations incorporate thermal fluctuation into macroscopic hydrodynamics by the addition of white noise fluxes whose magnitudes are set by a fluctuation–dissipation theorem. The study focuses on capturing the correct variance and correlations computed at equilibrium flows, which are compared with available theoretical values. Moreover, a numerical test for the random walk of standing shock wave has been considered for capturing the shock location.  相似文献   
44.
Percussion laser drilling, being a thermal process, produces holes having widely differing characteristics than that of the mechanically drilled holes. In the present study, on the percussion laser drilling of through holes in a nickel-based superalloy (SUPERNI 263A), 21 characteristics were identified, and the methods of their determination were proposed. The effect of peak power of laser pulses on the identified hole characteristics were studied.  相似文献   
45.
Keeping in mind the significance of hydrogels as an external stimuli sensitive super absorbing material, some transparent covalent hydrogels of chitosan were prepared by crosslinking with varying amounts of formaldehyde solution used as crosslinking agent. The characteristics of hydrogels were investigated by Fourier transform infrared (FT-IR) spectroscopy and swelling experiments. The effect of crosslinking agent on water absorbency has been investigated. The hydrogels exhibited a relatively higher swelling ratio in the range of 2066–3306% and equilibrium water content (EWC) in the range of 95-38–97 06% at pH 7 and 35°C temperature. The influence of external stimuli such as pH, temperature, and ionic strength of the swelling media on equilibrium swelling properties has been observed. Hydrogels showed a typical pH and temperature responsive behaviour such as low pH and high temperature has maximum swelling while high pH and low temperature show minimum swelling. An increase in the ionic strength of swelling media caused a continuous decrease in the swelling of hydrogels at both acidic and basic pH.  相似文献   
46.
The design, refurbishment and future decommissioning of nuclear reactors are crucially concerned with reducing the risk of radiation exposure that can result in adverse health effects and potential loss of life. To address this concern, large financial investments have been made to ensure safety of operating nuclear power plants worldwide. The efficacy of the expenditures incurred to provide safety must be judged against the safety benefit to be gained from such investments. We have developed an approach that provides a defendable basis for making that judgement.If the costs of risk reduction are disproportionate to the safety benefits derived, then the expenditures are not optimal; in essence the societal resources are being diverted away from other critical areas such as health care, education and social services that also enhance the quality of life. Thus, the allocation of society’s resources devoted to nuclear safety must be continually appraised in light of competing needs, because there is a limit on the resources that any society can devote to extend life.The purpose of the paper is to present a simple and methodical approach to assessing the benefits of nuclear safety programs and regulations. The paper presents the Life-Quality Index (LQI) as a tool for the assessment of risk reduction initiatives that would support the public interest and enhance both safety and the quality of life. The LQI is formulated as a utility function consistent with the principles of rational decision analysis. The LQI is applied to quantify the societal willingness-to-pay (SWTP) for safety measures enacted to reduce of the risk of potential exposures to ionising radiation. The proposed approach provides essential support to help improve the cost–benefit analysis of engineering safety programs and safety regulations.  相似文献   
47.
48.
Most developing countries such as India use biomass as a primary source of energy especially in domestic sectors in the rural area. The increasing population exerts more pressure on the biomass resource thereby initiating energy crisis in the region. The issue of shortage of fuelwood in the remote mountain regions is increasing since the alternative energy resources have limitations either due to poor economic condition of the people, complex technology involved or being inaccessible due to remoteness. It is also seen that the use of traditional biomass as a source of energy will improve the livelihood conditions of the people and it will give ecological benefits to the region if other associated factors like health, gender etc. are taken care of and thus the planners aim to focus on sustaining the natural fuelwood resources. The present paper attempts to predict the future fuelwood demand based on the present consumption pattern in the upland villages of Indian Himalaya. Major consumption characteristics such as fuelwood consumption at different altitude and per capita fuelwood consumption (PCFC) are studied. Population dynamics model is postulated in order to assess future population vs. fuelwood consumption scenario, thereby projecting the future population and the future fuelwood demand in the region.It is observed that variations in fuelwood consumption exist at different altitudes in the hilly region. Mathematical modelling and time-series simulation model was proposed and validated model to predict the future expected demand of fuelwood resources in Phakot watershed. Based on the projected population and season based fuelwood requirements, the watershed will have a total fuelwood demand of 19,327 t in 2011 which is expected to reach 36,462 t in 2021. Such studies on the future resource demand trends will help in finding suitable region-specific and need-based alternative strategies for achieving sustainable fuelwood management at the micro-level.  相似文献   
49.
We investigated the size dependent ferromagnetism in dodecyl amine capped zinc oxide nanoparticle. X-ray diffraction and X-ray photoelectron spectroscopy analysis demonstrated that density of oxygen vacancies was enhanced due to an increase in compressive strain concomitant with the decrease in particle size. Magnetic measurements showed increased ferromagnetic ordering in ZnO nanoparticles with reduced particle size. It was also found that the increase in coercive field, saturation magnetization and magnetic hysteresis loop area were invariably associated with increased oxygen defect population. The observed ferromagnetism in organic capped zinc oxide nanocrystals has therefore been assigned to defect induced phenomena. Results of sample characterization using optical absorption spectroscopy, photo luminescence spectroscopy and high resolution transmission electron microscope have also been presented.  相似文献   
50.
In this article, we made a comparative study of two multiple myeloma drugs: lenalidomide and pomalidomide. We calculated and discussed their geometries at DFT/B3LYP method. Intra-molecular hydrogen bonding in these molecules is confirmed and characterized by QTAIM calculations. Electronic parameters along with HOMO-LUMO and MESP surfaces are calculated in order to compare their chemical reactivity. The effect of structure and bonding on electronic properties and biological activities is discussed and it is established that pomalidomide is more biologically active than lenalidomide. The phenyl ring of these molecules show teratogenic effects, making a possibility of finding another new class of drugs.  相似文献   
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